Air-conditioning control apparatus

ABSTRACT

An air-conditioning control apparatus performs detailed determination of the operating conditions of an air-conditioning apparatus, and performs efficient air-conditioning control such that power distribution is changed based on the detailed determination, in order to improve the comfort of occupants under a limitation on air-conditioning, thereby balancing ensuring the range with ensuring the comfort of the occupants. The air-conditioning control apparatus calculates usable power amounts for a cooling unit and a heating unit, and drives the cooling unit and the heating unit based on drive limit values. It allocates power amounts calculated for the condition of the battery and the vehicle drive, that can be allocated to the air-conditioning equipment, to the cooling unit and the heating unit according to an air-conditioning state that is set automatically or manually, thereby enabling necessary heating and cooling to be used to its full extent even during limitations on air-conditioning.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority from JP 2011-063999 filed in the Japanese Patent Office on Mar. 23, 2011, the disclosure of which is hereby incorporated herein by reference.

BACKGROUND OF THE INVENTION

The contents disclosed below relate to an air-conditioning control apparatus, and more specifically, relate to an air-conditioning control apparatus that performs air-conditioning control in a motor vehicle such as an electric vehicle (EV) or a hybrid electric vehicle (HEV).

In motor vehicles such as electric vehicles (EV) and hybrid electric vehicles (HEV), in order to prioritize vehicle traveling with low battery charge, a limitation on air-conditioning equipment such as an auxiliary heater (PTC) or an electric compressor is required. When a limitation on the air-conditioning equipment is enforced, heating and cooling are both limited to a minimum driving state (minimum electric power value of the electric compressor and the auxiliary heater), regardless of the vehicle traveling state and power generation state (in the case of an HEV vehicle). In this situation, operation of the air-conditioning equipment is uniformly limited regardless of the panel settings set by the driver, and the power required for cooling and heating performance determined according to outside air temperature, etc.

That is to say, as a result of limiting air-conditioning based on simply determining whether or not the power limitation is performed, when the air-conditioning is performed, a drive control amount for the limitation is set to a value obtained by simply limiting a drive control amount in the normal air-conditioning control, and the limitation is performed uniformly with respect to all states having different conditions.

In a hybrid vehicle according to Japanese Laid-open Patent Application Publication No. 1997-76740, power for a cooling unit is provided from a battery that supplies power to a driving electric motor, in order to effect cooling.

An air-conditioning apparatus for a hybrid vehicle according to Japanese Patent No. 3791234 calculates the power required for air-conditioning that is required by an air-conditioning unit for adjusting compartment temperature to a preset temperature, and during vehicle traveling, sets a higher target remaining battery charge with an increase of the power required for air-conditioning.

In summer season, when an auxiliary heater serving as a heating unit is not used, and only an electric compressor serving as a cooling unit is required, the driving power allocated for the auxiliary heater can be added to the electric compressor side. However, in the conventional technique, even in such a case, the electric compressor is limited to a minimum power value in the minimum driving state, even though the driving power allocated for the auxiliary heater can be added to the electric compressor side. Moreover, even if battery charge sufficiently remains, or power generation is possible as in the hybrid electric vehicle (HEV), limitation may be enforced so that all operations of the air-conditioning equipment are suspended.

The air-conditioning control apparatus includes a defroster mode for increasing defogging properties (defogging performance) and a defroster and foot mode (D/F mode) as selectable air outlet modes. In these modes, control of condensation (moisture) contained in the air is executed. That is to say, control is executed so that a cooling unit constituting a cooling cycle system of the air-conditioning apparatus is driven, and a heating unit of the air-conditioning apparatus is driven for raising the temperature of air cooled by the cooling cycle system to a target air outlet temperature. In the defroster mode or the D/F mode, the cooling unit and the heating unit need to be driven simultaneously, and power is required for both cooling and heating systems, and hence, the power consumption is substantial.

As a result, if the above limitation on air-conditioning is enforced while executing the defroster mode or the D/F mode, substantial functions of the mode may be compromised. If the defroster mode or the D/F mode does not function substantially due to the limitation on air-conditioning, the defogging properties decrease. From a standpoint of ensuring visibility during driving, air-conditioning performance must be ensured to avoid a decrease in defogging properties under specific conditions.

In the air-conditioning control based on simply determining whether or not to perform the power limitation, detailed determination of the operating conditions of the air-conditioning apparatus or the like is not performed, and air-conditioning control in which the power distribution is changed based on the detailed determination is not performed. In the current limitation on air-conditioning, cruising distance can be extended corresponding to a reduction in the amount of power consumed by the air-conditioning. However, in the case in which sufficient power can be ensured without problems of traveling, air-conditioning control for maintaining comfort cannot be performed, or conversely, the air-conditioning control may reduce comfort.

In view of the above situation, there is proposed an air-conditioning control apparatus that performs detailed determination of the operating conditions, etc., of the air-conditioning apparatus, and performs efficient air-conditioning control such that power distribution is changed based on the detailed determination, in order to improve the comfort of occupants under a limitation on air-conditioning, thereby balancing ensuring the cruising distance with ensuring the comfort of the occupants.

BRIEF SUMMARY OF THE INVENTION

An air-conditioning control apparatus disclosed herein is used for a vehicle including an air-conditioning apparatus driven by using power that can be supplied to an on-board battery or power supplied from the battery, in which the air-conditioning apparatus includes at least a cooling unit driven by power when a cooling system operates, and a heating unit driven by power when a heating system operates, in which the air-conditioning control apparatus executes control for limiting power to be supplied to the air-conditioning apparatus at least when a state of charge of the battery is low.

In this control for limiting power, the air-conditioning control apparatus calculates a usable power amount for air-conditioning; calculates a usage proportion of the cooling unit, and calculates a usable power amount for the cooling unit based on the usable power amount for air-conditioning and the usage proportion of the cooling unit; calculates a usage proportion of the heating unit, and calculates a usable power amount for the heating unit based on the usable power amount for air-conditioning and the usage proportion of the heating unit; calculates a target cooling power amount; sets a difference between the usable power amount for the cooling unit and the target cooling power amount as a power difference of the cooling unit, and designates the target cooling power amount as a driving limit value for cooling, to drive the cooling unit, when the target cooling power amount is less than the usable power amount for the cooling unit; sets the power difference of the cooling unit to zero, and designates a sum of the usable power amount for the cooling unit and a power difference of the heating unit as a driving limit value for cooling, to drive the cooling unit, when the target cooling power amount exceeds the usable power amount for the cooling unit; calculates a target heating power amount; sets a difference between the usable power amount for the heating unit and the target heating power amount as the power difference of the heating unit, and designates the target heating power amount as a driving limit value for heating, to drive the heating unit, when the target heating power amount is less than the usable power amount for the heating unit; and sets the power difference of the heating unit to zero, and designates a sum of the usable power amount for the heating unit and the power difference of the cooling unit as a driving limit value for heating, to drive the heating unit, when the target heating power amount exceeds the usable power amount for the heating unit.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a functional block diagram illustrating an air-conditioning control apparatus;

FIG. 2 is a schematic diagram illustrating an air-conditioning apparatus and the air-conditioning control apparatus mounted on a vehicle;

FIG. 3 illustrates a usage proportion of a cooling unit in the case of an automatic air-conditioning system;

FIG. 4 illustrates a usage proportion of a cooling unit in the case of a manual air-conditioning system;

FIG. 5 is a flowchart for calculating a usable power amount for a cooling unit and a usable power amount for a heating unit;

FIG. 6 is a flowchart for calculating a driving limit value for cooling; and

FIG. 7 is a flowchart for calculating a driving limit value for heating.

DETAILED DESCRIPTION

An air-conditioning control apparatus disclosed here performs detailed determination of operating conditions or the like of an air-conditioning apparatus so as to improve the comfort of occupants under a limitation on air-conditioning, and performs efficient air-conditioning control by changing power distribution or the like based on the detailed determination so as to balance ensuring the range with ensuring the comfort of the occupants. That is to say, the air-conditioning control apparatus according to the present embodiment realizes an object of performing detailed determination of the operating conditions or the like of the air-conditioning apparatus, performing efficient air-conditioning control by changing power distribution or the like based on the detailed determination, and balancing ensuring the range with ensuring the comfort of occupants, by calculating usage proportions of a cooling unit and a heating unit, so that comfort of the occupants is improved under a limitation on air-conditioning.

In FIG. 1 and FIG. 2, a motor vehicle (hereinafter, referred to as a “vehicle”) 1 is an electric vehicle or a hybrid vehicle. A windshield 2 and a vehicle interior 3 thereof are shown in FIG. 2.

On the vehicle 1 there is mounted a power train 4 including a drive motor and a transmission for traveling, an air-conditioning apparatus (air-conditioner) 5 that performs air-conditioning of the vehicle interior 3, and a battery 6.

As shown in FIG. 2, the air-conditioning apparatus 5 performs air-conditioning of the vehicle interior 3 by performing dehumidifying, cooling, or heating based on air temperature and relative humidity in the vehicle interior 3, and includes a path forming body 8 that forms an air circulation path 7.

The path forming body 8 is provided with an inside and outside air switching damper 13 that swings inside an upstream end of the path forming body 8, and an intake port actuator 14 that actuates the inside and outside air switching damper 13, so as to switch between an outside air introduction port 10 connected to an outside air introduction duct 9 and an inside air introduction port 12 connected to an inside air introduction duct 11. Moreover, the path forming body 8 is provided with a first outlet switching damper 19 that swings inside a downstream end of the path forming body 8 and a first mode actuator 20 that actuates the first outlet switching damper 19, so as to switch between a defroster outlet 16 connected to a defroster duct 15 and a vent outlet 18 connected to a vent duct 17. Furthermore, the path forming body 8 is provided with a second outlet switching damper 23 that swings inside the downstream end of the path forming body 8 and a second mode actuator 24 that actuates the second outlet switching damper 23, so as to open and close a foot outlet 22 connected to a foot duct 21. The same configuration can be realized by connecting the first mode actuator 20 and the second mode actuator 24 by a link mechanism to form one actuator.

In the path forming body 8, a blower fan 25, an evaporator 26, a heater core 27, an air mixing damper 28, and an automatic and manual (AM) actuator 29 are provided. The blower fan 25 is provided on a downstream side of the inside and outside air switching damper 13, and is driven by a fan motor 30 to feed air into the vehicle interior 3. The evaporator 26 is provided on the downstream side of the blower fan 25, and is used for cooling the vehicle interior 3. An electric compressor 32 constituting a cooling unit 31 for cooling the vehicle interior 3, is arranged outside the path forming body 8, and is connected to the evaporator 26. The heater core 27 is provided on the downstream side of the evaporator 26, and is driven for heating the vehicle interior 3. An auxiliary heater (PTC) 34 constituting a heating unit 33 is arranged near the downstream side of the heater core 27. The air mixing damper 28 is actuated by the automatic and manual (AM) actuator 29, and swings in the air circulation path 7 so as to adjust a quantity of airflow to the heater core 27.

The cooling unit 31 is driven by power when a cooling system of the air-conditioning apparatus 5 is used. The heating unit 33 is driven by power when a heating system of the air-conditioning apparatus 5 is used.

As shown in FIG. 1 and FIG. 2, in the vehicle 1 there is mounted an air-conditioning control apparatus 35 that controls the air-conditioning apparatus 5.

The air-conditioning control apparatus 35 includes a control device for power train 36 that communicates with the battery 6 and controls the power train 4, a control device for air-conditioning 37 that automatically or manually controls the air-conditioning apparatus 5, and an air-conditioning control device for a motor vehicle (corresponding to an EV controller or HEV controller) 38 that communicates with these control device for power train 36 and control device for air-conditioning 37. The air-conditioning control apparatus 35 drives the air-conditioning apparatus 5 by using power that can be supplied to the battery 6 or power supplied from the battery 6, and limits power to be supplied to the air-conditioning apparatus 5 at least when the state of charge of the battery 6 is low.

The control device for power train 36 includes a usable power amount for air-conditioning calculating section 36A, and a limitation determining section 36B that determines whether or not a limitation on power to be supplied to the air-conditioning apparatus 5 is being executed. The control device for power train 36 calculates a usable power amount for air-conditioning, which can be allocated to an air-conditioning (cooling and heating) system based on power generation control, power supply, vehicle drive control, power consumption, remaining amount of battery charge, charging state of battery, and the like.

The control device for air-conditioning 37 includes an automatic air-conditioning control device 39 to be used when the air-conditioning apparatus 5 is used as the automatic air-conditioning system, and a manual air-conditioning control device 40 to be used when the air-conditioning apparatus 5 is used as the manual air-conditioning system. The automatic air-conditioning control device 39 includes a panel operating section 39A operated by a driver, and a target air outlet temperature and air outlet calculating section 39B that communicates with an outside air temperature detection sensor 41. The manual air-conditioning control device 40 includes an operating panel 40A operated by the driver. The automatic air-conditioning control device 39 calculates a target air outlet temperature and an air outlet port (MODE state) based on panel operation performed by the driver by using the panel operating section 39A (an operation panel can be separately provided) and the outside air temperature detection sensor 41 (including general sensor items required as the automatic air-conditioning system), etc. The manual air-conditioning control device 40 calculates a MODE and an adjustment temperature (panel operation state) according to the MODE and the panel operation for temperature adjustment performed by the driver.

As shown in FIG. 1, the air-conditioning control device for motor vehicle 38 includes a power amounts calculating section 38A that calculates a target cooling power amount and a target heating power amount, a state determining section 38B that determines a temperature adjusted state and an air outlet (MODE) state, a usage proportions calculating section 38C that calculates a usage proportion of the cooling unit 31 and a usage proportion of the heating unit 33, and a usable power amounts calculating section 38D that calculates a usable power amount of the cooling unit 31 and a usable power amount of the heating unit 33.

The air-conditioning control device for motor vehicle 38 communicates with the electric compressor 32 as the cooling unit 31 and the auxiliary heater 34 as the heating unit 33, and calculates a target cooling power amount (power amount of the electric compressor 32) and a target heating power amount (power amount of the auxiliary heater (PTC or the like) 34) required by automatic air-conditioning and manual-air conditioning, based on evaporator-thermistor temperature and water temperature, etc. Moreover, in the case of the automatic air-conditioning system, the air-conditioning control device for motor vehicle 38 calculates a usage proportion X of the cooling unit shown in FIG. 3 based on the target air outlet temperature and the MODE (air outlet) state calculated by the automatic air-conditioning control device 39 (X is set between 0% and 100%). In the defroster (DFR) mode and the defroster and foot (D/F) mode of the various MODEs, the usage proportion of the cooling unit 31 is set to be larger for giving priority to antifogging performance. On the other hand, in the case of the manual air-conditioning system, the air-conditioning control device for motor vehicle 38 calculates the usage proportion of the cooling unit 31 shown in FIG. 4 based on the MODE and the adjustment temperature set by the driver (X is set between 0% and 100%).

The usage proportion of the heating unit 33 is calculated based on a value obtained by subtracting the calculated usage proportion X % of the cooling unit 31 from 100% (usage proportion of heating unit=100%−X %).

In calculation of the usable power amount for air-conditioning, because the value fluctuates greatly, changes in values can be suppressed by providing an averaging process. Moreover, when no limitation on air-conditioning is in execution, no limitation on the air-conditioning equipment is performed. Hence, the following process may be performed just when a limitation on air-conditioning is in execution.

The air-conditioning control device for motor vehicle 38 calculates the usable power amount for the cooling unit and the usable power amount for the heating unit based on the average usable power amount for air-conditioning calculated via the averaging process, the usage proportion of the cooling unit 31, and the usage proportion of the heating unit 33 (refer to FIG. 5).

The air-conditioning control device for motor vehicle 38 compares the calculated usable power amount for the cooling unit with the calculated target cooling power amount. In the case in which the target cooling power amount is greater than the usable power amount of the cooling unit, the air-conditioning control device for motor vehicle 38 sets the power difference of the cooling unit that can be supplied to the heating unit 33 to zero (0), and sets the driving limit value for cooling to a sum of the usable power for the cooling unit and the power difference of the heating unit (refer to FIG. 6). The air-conditioning control device for motor vehicle 38 drives the cooling unit 31 according to the driving limit value for cooling.

On the other hand, in the case in which the target cooling power amount is less than or equal to the usable power amount for the cooling unit, the air-conditioning control device for motor vehicle 38 supplies the reminder of the usable power amount of the cooling unit (the power difference of the cooling unit) to the heating unit 33 side, and drives the cooling unit 31 by designating the target cooling power amount as the driving limit value for cooling, as in the case of no limitation.

The air-conditioning control device for motor vehicle 38 fixes a driving limit value for heating in the same manner as for the cooling unit 31 (refer to FIG. 7).

As shown in FIG. 1, the air-conditioning control apparatus 35 according to the present embodiment including the air-conditioning control device for motor vehicle 38, controls the electric compressor 32 and the auxiliary heater (PTC or the like) 34 as the air-conditioning equipment that performs cooling and heating, in association with the operating panel, etc., operated by the driver (only the operating panel is connected in the case of a vehicle with manual air-conditioning control), management of the battery state, and drive control of the vehicle. The air-conditioning control apparatus 35 allocates the power amount that can be allocated to the air-conditioning system, which is calculated according to the state of the battery 6 and the vehicle driving state, to cooling (driving power of the electric compressor 32) and heating (driving power of the auxiliary heating unit 34) according to a driver demand or the automatic air-conditioning state, and performs control so that the required heating and cooling can be realized as much as possible even under a limitation on air-conditioning.

To explain specifically, in the case in which the usable power amount for air-conditioning and the usage proportion of the cooling unit 31 has been calculated, the air-conditioning control apparatus 35 calculates the usable power amount for the cooling unit 31 based on the usable power amount for air-conditioning and the usage proportion of the cooling unit 31. Moreover, the air-conditioning control apparatus 35 calculates the usage proportion of the heating unit 33 and calculates the usable power amount for the heating unit 33 based on the usable power amount for air-conditioning and the usage proportion of the heating unit 33.

The usage proportion of the cooling unit 31 is set based on the target air outlet temperature, or a physical amount corresponding thereto and the selected air outlet mode. In this case, the usage proportion of the heating unit 33 is a difference obtained by subtracting the usage proportion of the cooling unit 31 from “1” as a whole, that is, 100%. In this calculation, particularly, when the selected air outlet mode includes a defroster, such as the defroster mode or the defroster and foot mode (D/F mode), the usage proportion of the cooling unit 31 is set to be larger than the other air outlet mode.

Moreover, the air-conditioning control apparatus 35 calculates the target cooling power amount. When the target cooling power amount is equal to or less than the usable power amount for the cooling unit 31, the air-conditioning control apparatus 35 sets the difference between the usable power amount for the cooling unit 31 and the target cooling power amount as a power difference of the cooling unit, and designates the target cooling power amount as the driving limit value for cooling, to derive the cooling unit 31. On the other hand, when the target cooling power amount exceeds the usable power amount for the cooling unit 31, the air-conditioning control apparatus 35 sets the power difference of the cooling unit to zero (0), and designates a sum of the usable power amount for the cooling unit 31 and the power difference of the heating unit as the driving limit value for cooling, to drive the cooling unit 31. Consequently, if the power difference of the heating unit is usable, the driving limit value for cooling can be set by adding the power difference of the heating unit to the usable power amount for the cooling unit 31.

Moreover, the air-conditioning control apparatus 35 calculates the target heating power amount. When the target heating power amount is equal to or less than the usable power amount for the heating unit 33, the air-conditioning control apparatus 35 sets the difference between the usable power amount for the heating unit 33 and the target heating power amount as a power difference of the heating unit, and designates the target heating power amount as a driving limit value for heating, to drive the heating unit 33. On the other hand, when the target heating power amount exceeds the usable power amount for the heating unit 33, the air-conditioning control apparatus 35 sets the power difference of the heating unit to zero (0), and designates a sum of the usable power amount for the heating unit 33 and the power difference of the cooling unit as the driving limit value for heating, to drive the heating unit 33. Consequently, if the power difference of the cooling unit is usable, the driving limit value for heating can be set by adding the power difference of the cooling unit to the usable power amount for the heating unit 33.

Calculation of the usable power amount for the cooling unit 31 and the usable power amount for the heating unit 33 will be explained with reference to the flowchart in FIG. 5.

As shown in FIG. 5, when the program is started (Step A01), the air-conditioning control apparatus 35 determines whether or not a limitation in power to be supplied to the air-conditioning apparatus 5 is in execution (Step A02). When it is NO in Step A02, the determination is continued. When it is YES in Step A02, the air-conditioning control apparatus 35 calculates the usable power amount for air-conditioning (Step A03), and calculates an averaged usable power amount for air-conditioning by a filtering process (Step A04). The air-conditioning control apparatus 35 then calculates a usage proportion X % of the cooling unit 31 (Step A05), and calculates the usage proportion of the heating unit 33 as 100%−X % (Step A06). Thereafter, the air-conditioning control apparatus 35 calculates the usable power amount for the cooling unit 31 as “averaged usable power amount for air-conditioning×usage proportion X % of cooling unit 31” (Step A07), and calculates the usable power amount for the heating unit 33 as “averaged usable power amount for air-conditioning×usage proportion of heating unit 33 (100%−X %)” (Step A08), and then returns the program (Step A09).

Next, calculation of the driving limit value for cooling will be explained with reference to the flowchart in FIG. 6.

As shown in FIG. 6, when the program is started (Step B01), the air-conditioning control apparatus 35 checks a state of a limitation in power to be supplied to the air-conditioning apparatus 5 (Step B02). When it is YES in Step B02 (the limitation is in execution), the air-conditioning control apparatus 35 calculates the target cooling power amount (Step B03), and determines whether the target cooling power amount exceeds the usable power amount for the cooling unit 31 (Step B04). When it is YES in Step B04, the air-conditioning control apparatus 35 sets the power difference of the cooling unit to zero (0) (Step B05), and designates “usable power amount for the cooling unit 31+power difference of the heating unit” as the driving limit value for cooling (Step B06), and a state of a limitation on air-conditioning is in execution (Step B07). On the other hand, when it is NO in Step B04, the air-conditioning control apparatus 35 calculates the power difference of the cooling unit as “usable power amount for the cooling unit 31−target cooling power amount” (Step B08). After the process in Step B08, or when it is NO in step B02 (the limitation is not in execution), the air-conditioning control apparatus 35 calculates the driving limit value for cooling (Step B09), and a state of a limitation on air-conditioning is not in execution (Step B10). After the process in Step B07, or after the process in Step B10, the air-conditioning control apparatus 35 returns the program (Step B11).

Next, calculation of the driving limit value for heating will be explained with reference to the flowchart in FIG. 7.

As shown in FIG. 7, when the program is started (Step C01), the air-conditioning control apparatus 35 checks a state of a limitation in power to be supplied to the air-conditioning apparatus 5 (Step C02). When it is YES in Step C02 (the limitation is in execution), the air-conditioning control apparatus 35 calculates the target heating power amount (Step C03), and determines whether the target heating power amount exceeds the usable power amount for the heating unit 33 (Step C04). When it is YES in Step C04, the air-conditioning control apparatus 35 sets the power difference of the heating unit to zero (0) (Step C05), and designates “usable power amount for the heating unit 33+power difference of the cooling unit” as the driving limit value for heating (Step C06), and a state of a limitation on air-conditioning is in execution (Step C07). On the other hand, when it is NO in Step C04, the air-conditioning control apparatus 35 calculates the power difference of the heating unit as “usable power amount for the heating unit 33−target heating power amount” (Step C08). After the process in Step C08, or when it is NO in step C02 (the limitation is not in execution), the air-conditioning control apparatus 35 calculates the driving limit value for heating (Step C09), and a state of a limitation on air-conditioning is not in execution (Step C10). After the process in Step C07, or after the process in Step C10, the air-conditioning control apparatus 35 returns the program (Step C11).

The embodiment of the air-conditioning control apparatus disclosed above will be explained together with aspects of the invention.

Aspect 1

The air-conditioning control apparatus 35 calculates a usable power amount for air-conditioning (mean value thereof).

The air-conditioning control apparatus 35 calculates a usage proportion of the cooling unit 31, and calculates a usable power amount for the cooling unit 31 based on the usable power amount for air-conditioning and the usage proportion of the cooling unit 31.

The air-conditioning control apparatus 35 calculates a usage proportion of the heating unit 33, and calculates a usable power amount for the heating unit 33 based on the usable power amount for air-conditioning and the usage proportion of the heating unit 33.

The air-conditioning control apparatus 35 calculates a target cooling power amount. When the target cooling power amount is less than the usable power amount for the cooling unit 31, the air-conditioning control apparatus 35 sets a difference between the usable power amount for the cooling unit 31 and the target cooling power amount as a power difference of the cooling unit, and designates the target cooling power amount as a deriving limit value for cooling, to drive the cooling unit 31. On the other hand, when the target cooling power amount exceeds the usable power amount for the cooling unit 31, the air-conditioning control apparatus 35 sets the power difference of the cooling unit to zero, and designates a sum of the usable power amount for the cooling unit 31 and a power difference of the heating unit as a driving limit value for cooling, to drive the cooling unit 31.

The air-conditioning control apparatus 35 calculates a target heating power amount. When the target heating power amount is less than the usable power amount for the heating unit 33, the air-conditioning control apparatus 35 sets a difference between the usable power amount for the heating unit 33 and the target heating power amount as the power difference of the heating unit, and designates the target heating power amount as a driving limit value for heating, to drive the heating unit 33. On the other hand, when the target heating power amount exceeds the usable power amount for the heating unit 33, the air-conditioning control apparatus 35 sets the power difference of the heating unit to zero, and designates a sum of the usable power amount for the heating unit 33 and the power difference of the cooling unit as a driving limit value for heating, to drive the heating unit 33.

Consequently, under power limitations in which power that can be used for the air-conditioning apparatus 5 is limited, power distribution to be used for heating and cooling can be set to an appropriate distribution or can be approximated to a distribution similar thereto. Moreover, power (power difference) on one side of the heating unit and the cooling unit, having power to spare with respect to the target power can be transferred to the other side thereof, and a higher capacity of the air-conditioning apparatus 5 can be ensured, thereby enabling to ensure comfort and visibility even when there is power limitation.

Aspect 2

The air-conditioning control apparatus 35 sets the usage proportion of the cooling unit 31 based on a target air outlet temperature, or a physical amount corresponding thereto, and an air outlet mode, and the usage proportion of the heating unit 33 is set to a difference obtained by subtracting the usage proportion of the cooling unit 31 from “1” as a whole.

The usage proportions of the cooling unit 31 and the heating unit 33 can be set based on the target air outlet temperature or, for example, an adjusted temperature, which is a physical amount corresponding thereto, and the air outlet mode, regardless of whether automatically or manually, and power distribution can be set to an appropriate distribution or approximated to the appropriate distribution.

Aspect 3

In an air outlet mode including a defroster, the air-conditioning control apparatus 35 sets the usage proportion of the cooling unit 31 to be larger than in other air outlet modes.

Accordingly, the usage proportion can be set so that antifogging properties can be ensured according to the selected air outlet mode.

In the embodiment described above, when antifogging performance is given priority and the defroster (DFR) mode is selected, a setting is also possible when the usage proportion of the cooling unit (driving rate of the electric compressor) is set to 100% in a separate map.

Moreover, a driver selection switch can be provided to select whether to use the control described in the above embodiment, so that control selection such as for uniformly limiting the operation of the air-conditioning equipment to minimum driving, or stopping the operation of the air-conditioning equipment in a conventional manner, is possible.

The air-conditioning control apparatus according to the present invention is applicable to various vehicles having a battery, for example, a motor vehicle such as an electric vehicle or a hybrid vehicle. In the case of the hybrid vehicle, an internal combustion engine is provided in a power train of the vehicle, and heat of cooling water or the like is supplementally used for the air-conditioning apparatus.

Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. 

1. An air-conditioning control apparatus for a vehicle comprising an air-conditioning apparatus driven by using power that can be supplied to an on-board battery or power supplied from the battery, in which the air-conditioning apparatus includes at least a cooling unit driven by power when a cooling system operates, and a heating unit driven by power when a heating system operates, wherein the air-conditioning control apparatus executes control for limiting power to be supplied to the air-conditioning apparatus at least when the state of charge of the battery is low, in this control for restricting power, the air-conditioning control apparatus: calculates a usable power amount for air-conditioning; calculates a usage proportion of the cooling unit, and calculates a usable power amount for the cooling unit based on the usable power amount for air-conditioning and the usage proportion of the cooling unit; calculates a usage proportion of the heating unit, and calculates a usable power amount for the heating unit based on the usable power amount for air-conditioning and the usage proportion of the heating unit; calculates a target cooling power amount; sets a difference between the usable power amount for the cooling unit and the target cooling power amount as a power difference of the cooling unit, and designates the target cooling power amount as a driving limit value for cooling, to drive the cooling unit, when the target cooling power amount is less than the usable power amount for the cooling unit; sets the power difference of the cooling unit to zero, and designates a sum of the usable power amount for the cooling unit and a power difference of the heating unit as the driving limit value for cooling, to drive the cooling unit, when the target cooling power amount exceeds the usable power amount for the cooling unit; calculates a target heating power amount; sets a difference between the usable power amount for the heating unit and the target heating power amount as the power difference of the heating unit, and designates the target heating power amount as a driving limit value for heating, to drive the heating unit, when the target heating power amount is less than the usable power amount for the heating unit; and sets the power difference of the heating unit to zero, and designates a sum of the usable power amount for the heating unit and the power difference of the cooling unit as the driving limit value for heating, to drive the heating unit, when the target heating power amount exceeds the usable power amount for the heating unit.
 2. An air-conditioning control apparatus according to claim 1, wherein the usage proportion of the cooling unit is set based on a target air outlet temperature or a physical amount corresponding thereto and an air outlet mode, and the usage proportion of the heating unit is set to a difference obtained by subtracting the usage proportion of the cooling unit from “1” as a whole.
 3. An air-conditioning control apparatus according to claim 2, wherein, in an air outlet mode including a defroster, the usage proportion of the cooling unit is set to be larger than in other air outlet modes. 